Compact power unit



2 Sheets-Sheet 1 QN g 5 N E. A. ROCKWELL COMPACT POWER UNIT Dec. 5, 1950Filed Aug. 22, 1945 1366- 1950 E. A. ROCKWELL COMPACT POWER UNIT 2Sheets-Sheet 2 Filed Aug. 22, 1945 [Hz/671.2 0?" Kai ward Q. ocfr iwe W3 Patented Dec. 1950 COMPACT rowan UNIT Edward A. Rockwell, ShakerHeights, Ohio, as-

signor, by niesne assignments, to Borg-Warner Corporation, Chicago,111., a corporation of Illinois Application August 22, 1945, Serial No.611,984

My invention relates particularly to power units which are adapted toapply power for the operation of any desired type of device but whichare especially applicable for the operation of accessories of automotivevehicles, airplanes, etc. The object of my invention is to provide apower unit of the above character which is compact in construction andwhich may be applied wherever desired, especially because of its smalldimensions. A further object is to provide a power unit of smalldiameter for this purpose. Other objects are to provide devices of thischar- Claims. (Cl. 6054.6)

ing the same on the valve seat I, except when the valve stem l4 contactswith the end of the cylindrical chamber 8. A plurality of radial ports20 connect the valve chamber I! with an acter which involve a vacuumsuspended movable wall or plunger for applying the power by a pullingaction but which are aided by a subsidiary pusher plunger which may beeither vacuum suspended or air .suspended. Further objects of myinvention will appear from the detailed description of the samehereinafter.

While my invention is capable of embodiment in many different forms, forthe purpose of illustration I have shown only two forms thereof in theaccompanying drawings, in which:

Fig. 1 is a' diagrammatic vertical section of a power unit apparatusmade in accordance with my invention, in which a vacuum suspendedauxiliary power plunger is used in its off position; and

Fig. 2 is a diagrammatic vertical section of a modification thereof,utilizing an air suspended auxiliary power plunger showing the positionin which air has been admitted to the relay valve.

In the drawings, referring first to Fig. '1, in which the power plungersare both normally vacuum suspended, I have shown a pedal i mounted on apedal lever 2 supported by a fixed pivot 3 from the chassis of anautomobile. The pedal lever 2 is connected by a piston rod 4 to a piston(not shown) in the usual type of master cylinder 5 having a reservoir 5and a vented removable filling cap 1. The master cylinder 5 is connectedby a pipe 8 to convey the hydraulic liquid under the manual pressurefrom the pedal I to a cylindrical chamber 9 in a plunger housing l0.Within the chamber 9 there is provided a manually operable plunger I Ihaving on its right hand end a plurality of spaced projections I! whichcontact with the end of the cylindrical chamber 9 in retracted position.Also, in the plunger. ii there is a central passageway l3 for receivinga fluted valve stem l4 of a conical cutoff valve i5 which cooperateswith a valve seat ii on a shoulder H in the end of a valve chamber l8containing a helical spring I8 urging the said conical valve I5 towardthe right for seatannular space 2| around the plunger H and which has aport 22 connecting it to an intensified pressure cylinder 23.

A flange 24 is provided on the plunger housing l0 forsecuring tightlythereto a dished diaphragm casing '25 having a flange 25 for clampingthereon a flexible diaphragm 21 againsta flange 28 of another disheddiaphragm casing 28. The diaphragm casing 23 has a vacuum inlet port 30connected by a pipe 3| to a vacuum pipe 32, containing a vacuum checkvalve 33, and leading to a manifold 34 of an internal combustion engineused for driving the automobile. 4

The inner portion of the flexible diaphragm 2'! is securely fastenedwithin a recess 35 in a clamping plate 35 carrying a spring supportingplate 31, held in place by a screw 38', for supporting a helicalretracting spring 39, the other end of which is supported in a recess 40in the diaphragm casing 29 In the clamping plate 35, furthermore, thereis provided a pressure compensating diaphragm 4| having attached theretoa stem 42, the other end of which is supported in a cylindrical recess43 in the end of the manually operated plunger II. On the said stem 42,furthermore, there is a peripheral flange 44 to contact with an opening45 in' a valve-operat=- ing lever 46 carried on ears 4'! by means ofpivots 48 mounted on either side of the diaphragm clamping plate 38. Ascrew-threaded adjustable rod 49 is, also, carried in the lever 45 so asto limit the movement of the lever 45 by the rod 4% contacting with theclamping plate 36. On the end of the valve lever 45 there is a pivot 50connecting the same to a valve operating rod it having on the other endthereof a disc-shaped vacuum valve member 52 which cooperates with avalve seat 53 on a tubular valve member 55 passing through a valvechamber 55 in the clamp= ing plate 36 where it is supported by means ofa subsidiary diaphragm 55 supported at its periphery in the clampingplate 36 and fastened at its inner portion to the tubular valve member54. A helical spring 5! rests at one end against the tubular valvemember 54 and at its other end is supported by a shoulder 58 in thechamber 55. The right hand end of the tubular valve member 54 has adisc-shaped air inlet valve member 59 cooperating with a valve seat 50around an annular passageway 5| which connects the chamber 33 with achamber 32 within the diaphragm casing 23. An air passageway 33 isprovided in the clamping plate 33 which connects with an air passageway33 in an intensifying plunger rod 63 provided with an intensifyingpiston 33 in the pressure intensifying cylinder 23 and which has ahydraulic pressure fluid outlet conduit 31 leading to the wheel brakecylinders of the four wheels of the automobile (not shown) in the usualway. The intensifying piston rod 33 also has a plurality of radial ports33 leading to the chamber 23 on the right hand face of the piston 33which communicates with the outer air through a series of ports 33.Furthermore, the rod 33 passes through a tubular extension I3 having aflange II to which there is secured an end plate 12 having attachedthereto an auxiliary diaphragm casing 13 connected by means of a pipe 13to the vacuum pipe 3| and which may, if desired, have attached thereto avacuum reservoir I3 connected by a pipe 13 and a T-Joint II to said pipeI3. On the other end of the intensifying piston rod 33, there are aplurality of flanges l3 and I3 for fastening thereto diaphragmsupporting plates 33 and 3| carrying between the same a flexiblediaphragm 82, the outer periphery of which is secured between a flange33 on the auxiliary diaphragm casing 13 and a flange 33 on a secondauxiliary diaphragm casing 33 which is connected by a pipe 83 to thechamber 32 at the-right hand side of the flexible diaphragm 21. A plug31 closesthe end of the passageway 33 in the intensifying piston rod 33.

In the modification of my invention, as shown in Fig. 2, I have provideda similar power unit construction in which the auxiliary flexiblediaphragm 82 is mounted between the auxiliary diaphragm casings l3 and33 but in which the diaphragm 32 is normally air suspended. For thispurpose, accordingly, the auxiliary diaphragm casing 33 is provided withan air port 33 and the intensifying piston rod passageway 33 is open tothe air chamber in the diaphragm casing 83,

by the plug 31 above referred to being omitted therefrom.

Also, in this instance, instead of providing a vacuum from the manifold33, if desired a source of constant vacuum may be provided by a separateelectrical power means, and in fact, if desired, this separateelectrically driven power means may be substituted for the connection tothe intake manifold in the form of my invention as set, forth in Fig. 1.In Fig. 2, for this purpose there is shown attached to the vacuum pipe3I the vacuum check valve 33, as in the case of Fig. 1, but in thisinstance to said check valve 33 there is connected a pipe 39 leading tothe outlet side of a rotary vacuum pump 30 driven by an electric motor3| having a ground connection 32 and a wire 33 leading by a manuallyoperable switch 33 to a spring pressed vacuum cut-out electrical switch33 constructed in any suitable manner, the other terminal of which leadsby a wire 33 to a battery or other source of electric current 81connected by a wire 33 to a ground 33. This vacuum cut-out switch 33 isconnected by a pipe I03 tothe pipe 3| so that when a suflicient degreeof vacuum is attained in the pipe 3I the circuit through the wires 33and 83 is broken by a pressure responsive element until the desiredlevel of vacuum is no longer present in the pipe 3|, whereupon the theelectric motor 9| and drive the vacuum pump to restore the desireddegree of vacuum.

In this instance, furthermore, the diaphragm casing I3, instead of beingprovided with the vacuum pipe 13, has connected thereto a pipe IOI whichleads to an upper diaphragm casing I32 of a relay valve I33. The relayvalve I33. also, has a lower diaphragm casing I33 which is connected bya pipe I33 to the T-Joint Il leading to the vacuum reservoir 13 and alsoto the pipe 3|. Within the lower diaphragm casing I33 there is an endplate I33 having a vent I31 leading to the outer air. Controlled amountsof air are conveyed from the vent I" through a hollow stem I33reciprocable within the same and around which there is located a coilspring I33 connected to a diaphragm clamping plate III) which clamps inplace the inner portion of a diaphragm I I I, the outer periphery ofwhich is clamped between flanges H2 and H3 of the diaphragm casings I 02and I33, respectively. Furthermore, within the diaphragm clamping plateIII there is an air passageway II3 which conveys the air from the ventIII to a valve chamber 3 having therein a valve stem III for operating avacuum inlet valve Ill and an air inlet valve I I3, both of which areconstructed in the same manner as the valve 32, 33 and the valve 39, 33respectively, previously described herein. In this instance there is avalve operating lever I", like the valve operating lever 33, mounted onthe diaphragm clamping plate H3,

the end of which lever is connected to a compensating diaphragm I20 inthe same manner as in the case of the pressure compensating diaphragm3I, previously described herein. For this purpose, the diaphragm I23 hasa diaphragm rod I2l having a head I22 supported in an opening I23 in theend of the valve rod III. In this instance, there is a pivotalconnection I23 on the valve rod I I3 which is connected by adiaphragmoperated rod I23 having thereon disc-shaped clamping membersI23 and I21, which support the inner portion of a pressure responsivediaphragm. I23, the outer periphery of which is clamped between a lowercylindrical diaphragm casing I23 and an upper diaphragm casing I33. Theupper diaphragm casing I33, furthermore, has vent openings I3I and isprovided with a hollow extension I32 having therein a helical spring I33supported at its lower end on the diaphragm casing I33 and at its upperend against a flange I33 secured to the stem I23. Within the diaphragmcasing I23 there is a chamber I33 connected by a pipe I33 to the maindiaphragm casing 23.

In the operation of my invention, referring flrst to the form of myinvention as shown in Fig. 1, the manual movement of the pedal I willcause the main cylinder 3 to deliver the hydraulic liquid under manualpressure to the chamber 3, whereupon, inasmuch as the valve I3 is openin the retracted position of the manual plunger II, the hydraulic liquidwill be forced out through the ports 23 into the chamber 2| and thenceby the ports 22 to the intensifying cylinder 23 and therefrom by thepipe 31 to the wheel brake cylinders (not shown). As this pressureincreases, however, which takes place substantially immediately afterthe depression of the pedal I, the manual piston II will be moved to theleft, in Fig. 1, thereby closing the cut-off valve II and moving thevalve lever 33. Prior to the movement of the valve lever 33, vacuum willbe present on switch as will again complete the circuit through 1" bo hsides of the iaphra m 21 inasmiwb as the vacuum .is supplied theretoi'rom'the manifold 24 or the vacuum reservoir or both, through the pipe.8|, the check valve 88 maintaining trapped the vacuum which has beensupplied to the interior of the power unit in this way on the left faceof the diaphragm 21. Initially, this vacuum will alsobe present on theright side ofthe phragm 21in the chamber 52 due to the vacuum valve52,58 being initially in open position.

When, as above referred to, the valve lever 48 will have been moved dueto the increase of the manual pressure applied to the pipe '8, thevacuum valve 52, 58 will become closed while the air valve 58, 58 isalso closed, and further pressure from the pipe 8 will, thereafter,unseat the air valve 58, 58, thus admitting air from the air vent 88through the ports 88, passageway 64 and passageway 88. In this waycontrolled amounts of atmospheric air pressure are admitted to thechamber 52 on the right face of the diaphragm 21, thus applying power tothe intensifying piston due to the smaller size of the piston 66 ascompared with the diaphragm 21. In this way the intensified hydraulicliquid pressure is conveyed by the pipe 61 to apply power to the wheelbrake cylinders on the ,four wheels of the automobile after the brakeshave been can be applied for the operation of the wheel brakes. Thisintensified pressure is, also, aided and increasedby the auxiliarydiaphragm 82, to the right'face of which there is applied the samecontrolled amounts of atmospheric air pressure by means of the pipe 86,the left face of the diaphragm 82 being supplied at all times by vacuumthrough the pipe 14, as in the case oi 6 8| and the reservoir 15. Inthis instance, the

diaphragm 21-.supplies the power pressure hytensifying plunger rod 85 bymeans of the air suspended diaphragm 82. In other words, in thisinstance atmospheric air pressure is always supplied to the right faceof the diaphragm 82 by .the vent 88 and controlled'amounts of vacuum aresupplied to the left face of the diaphragm "by the pipe IIII. The amountof the vacuum pressure thus admitted through the pipe IN is determinedby the air pressure in the pipe I88 from the diaphragm casing 25 hearingon the flexible diaphragm I28. This controls the vacthe left face, also,of the diaphragm 21. In any one desiredposition for the application ofpower pressurethrough the pipe 51 to the wheel brake cylinders, it willbe understood that the the pipe 8 are not beingincreased or decreased.When it is desired to relax the pressures on the wheel brake cylinders,the manual pressure on the pedal I is relaxed to the desired extent,whereupon some of the hydraulic pressure on the manual plunger II willbe relaxed, thus admitting additional vacuum through the valve 52, 53 tothe chamber 62 on the right face of the diaphragm 21. when the manualpressure is removed entirely from the pedal I the manual plunger II willbe retracted to the right hand end of the cylinder 8 by the force of thespring 88 and the liquid in the system will become uum may be supplied,instead of from the intake manifold 84, by means of the vacuum pump 88driven by the electric motor iii, the operation of which is controlledby the vacuum cutout electric switch 85 which completes the circuit todrive the motor 8i and operate the pump 88 only when insuflicient levelsof vacuum are being supplied to the pipe I80 through the pipe uumadmitted bymeans of the diaphragm rod I25 moving the valve lever M8 toclose the normally open air valve I I8 which normally supplies air tothe left face of the diaphragm 82, after which further movement-of -thevalve lever 8 opens the vacuum valve 1 to admit controlled] amounts ofvacuum from the lower diaphragm casing I84 to the upper diaphragm casingI02 and thence through the pipe I to the diaphragm casing 13, thussupplying added power' to the intensifying plunger rod 85. In any oneposition of the pedal I, the valves II8, as well as II1, will assumelapped position, as in the case, also, of the valves 52, 53 and 58, 80.Upon any relaxation of the manual pressure on the pedal I the air valveII8 will become opened tosome extent, thereby conveying some air pres.-sure through the pipe IIII to the left face of the diaphragm 82 at thesame time that some additional vacuum pressure is admitted'to the right7 face of the diaphragm 21 through the vacuum valve 52, 53, thusdecreasing to the extent de-v siredthe braking effect. Upon entirelyrelaxing the manual pressure on the pedal I, the air valve 8 will becomeopened and the-vacuum valve 52, 58 will likewise be open, thus restoringthe diaphragm 82 to its air suspended position and the diaphragm 21 toits vacuum suspended posi- While I have described my invention above inI the power unit adapted to be connected to a source of pressurediffering from the atmospheric pressure, a movable wall, an auxiliarymovable wall on the same axis as the first-mentioned wall, chambers forboth said walls, valve means controlling the application of saidpressure and atmospheric air to each! of the movable walls, manualhydraulic means for operating the valve means, and a hydraulicintensifier piston and cylinder located between the chambers of saidmovable walls, having a hydraulic connection to a device for performingwork. v 2. A power unit comprising a connection on the power unitadapted to be connected to a source of pressure differing from theatmospheric pressure, a movable wall, an auxiliary movable wall on thesame axis as the first-mentionedwall, chambers for both said walls, avalve means controlling the application of said pressure and atmosphericair to each of the movable walls, manual hydraulic means for operatingthe valve means, and a hydraulic intensifier piston and cylinder locatedbetween the said movable walls assault 7 having a hollow vented pistonrod extending to both said walls and a hydraulic connection to a devicefor performing work.

3. A power unit comprising a connection on the power unit adapted to beconnected to a source of pressure differing from the atmosphericpressure, a movable wall, an auxiliary movable wall on the same axis asthe first-mentioned wall, chambers for both said walls, a valve meanscontrolling the application of said pressure and atmospheric air to eachof the movable walls, manual hydraulic means for operating the -'valvemeans, and a hydraulic intensifier piston and cylinder located betweenthe said movable walls having a hollow vented piston rod extending toboth said walls and a hydraulic connection to a device for performingwork, said vented rod being in communication with an air port in thecylinder of said piston.

4. A power unit comprising a connection on the power unit adapted to beconnected to a source of pressure differing from the atmosphericpressure, a movable wall, an auxiliary movable wall on the same axis asthe first-mentioned wall, chambers for both said walls,.a valve meanscontrolling the application of said pressure and atmospheric air .toeach of the movable walls, manual hydraulic means for operatingthe-valve means including a pressure compensating diaphragm mounted onthe movable wall, a manually operated plunger and a valve lever at oneside of said piston, and a hydraulic"lntensifler piston and cylinderlocated between the said movable walls, having a hydraulic connection toa device for performing work.

5. A power unit comprising a connection onthe power unit adapted to beconnected to a source of pressure differing from the atmosphericpressure, a movable wall, an auxiliary movable wall on the same axis asthe first-mentioned wall, both of said walls being normally vacuumsusmeans, a hydraulic intensifier piston and cylinder located betweenthe said movable walls, having a hydraulic connection to a device forperforming work and a relay valve controlled by the atmospheric airadmitted to the first-mentioned wall and arranged to govern theadmission of said pressure to the auxiliary movable wall.

8. A power unit comprising a connection on the power unit adapted to beconnected to a source of vacuum, a movable wall, an auxiliary movablewall on the same axis as the first-mentioned wall, chambers for bothsaid walls, one of said walls being normally vacuum-suspended and theother normally air suspended, valve means controlling the application ofsaid vacuum and atmospheric able wall.

9. A power unit comprising a connection on the power unit adapted to beconnected to a source of fluid pressure differing from'the atmosphere, amovable wall, a cylinder therefor, a puller plunger having a hydraulicpiston connected to,

said wall having a hydraulic cylinder, another.

movable wall, a cylinder therefor, a pusher plunger connected to saidpiston, an inlet for-hydraulic liquid to control the power unit leadingto the hydraulic piston cylinder and a hydraulic outlet conduit fromsaid hydraulic piston cylinder to a part to perform work.

10. A power unit comprising a connection on the power unit adapted to beconnected to a source of fluid pressure differing from the atmospended,chambers for both said walls, a valve means controlling the applicationof said pressure and atmospheric air to each of the movable walls,manual hydraulic means for operating the valve means, and a hydraulicintensifier piston and cylinder located between the said movable wallsand having a hollow vented piston rod connected to both of said walls,having a hydraulic connection to a device for performing work.

6. A power unit comprising a connection on the power unit adapted to beconnected to a source of vacuum, a movable wall, an auxiliary movablewall, one of said walls being normally vacuum suspended and the othernormally air suspended, chambers for both said walls, valve meanscontrolling the' application of said vacuum and atmospheric air to eachof the movable walls, manual hydraulic means for operating the valvemeans, and a-hydraulic intensifier piston and cylinder located betweenthe chambers of saidphere, a movable wall, a cylinder therefor, a pullerplunger having a hydraulic piston connected to said wall having ahydraulic cylinder, another movable wall, a cylinder therefor, a pusherplunger connected to said piston, an inlet for hydraulic liquid tocontrol the power unit leading to the hydraulic piston cylinder and ahydraulic outlet conduit from said hydraulic piston cylinder to a partto perform work, said inlet having connected thereto a plunger operatedvalve mechanism for controlling the application of said fluid pressureto the said movable walls. EDWARD A. ROCKWELL.

REFERENCES crrsn The following references are of record in the file ofthis patent:

UNITED PATENTS France June 8; 1903

